Last Updated on October 6, 2023 by Matthew Lloyd

To clean underneath your car, start by pre-washing the undercarriage with a hose to soften dirt and grime. Then, use a degreaser to tackle any greasy or oily areas. Next, deep clean the undercarriage by accessing hard-to-reach spots with a wash mitt or brushes, thoroughly removing dirt and debris. Allow everything to dry before applying protective coatings, such as undercarriage dressing and WD-40, to prevent rust and corrosion. Additionally, take care of your tires and fender liners by cleaning them with dedicated cleaners. Finish by applying tire protection for enhanced appearance and longevity.

How To Clean Underneath Your Car: The Ultimate Guide

Step 1: Clean the Engine Bay

Before diving into the undercarriage, starting with a clean engine bay is important. This is crucial because any grime or dirt from the engine bay can trickle down onto the suspension and other components.

1. Wash your engine bay and remove loose debris.
2. Use an engine degreaser, such as Purple Power, to remove greasy or oily buildup.
3. Spray the degreaser onto the affected areas and let it sit for a few minutes.
4. Agitate the dirt and grime with a brush or sponge.
5. Rinse off the degreaser thoroughly with water.
6. Dry the engine bay with a clean microfiber cloth or allow it to air dry.

Step 2: Removing Wheels and Fender Liners

While not necessary, removing the wheels and fender liners provides easier access to hard-to-reach areas and ensures more thorough cleaning.

1. Safely jack up your car and secure it with jack stands.
2. Remove the wheels using the appropriate tools.
3. Take out the fender liners, which often accumulate dirt and debris.

Step 3: Pre-Wash and Degreasing

Before starting the deep cleaning process, it’s important to pre-wash the undercarriage to soften the dirt and grime.

1. Use a hose to spray down the undercarriage, focusing on removing loose dirt and debris.
2. Repeat the process to ensure thorough coverage.
3. Apply a degreaser like Purple Power to any greasy or oily areas.
4. Allow the degreaser to sit for a while to break down the buildup.
5. Rinse off the degreaser and any loosened dirt with a high-pressure jet setting on your hose.

Step 4: Deep Cleaning

Now comes the part that separates dedicated enthusiasts from the rest. Deep cleaning the undercarriage involves getting your hands dirty and reaching every nook and cranny.

1. Get a creeper or tool to access the car’s underside comfortably.
2. Start cleaning the undercarriage using a wash mitt, a long-handled brush, or a short-handled brush.
3. Pay attention to every reachable spot, removing dirt and grime.
4. Be thorough, especially in areas prone to debris buildup, such as bed and rocker panels.
5. Flush out any trapped debris by directing a stream of water from your hose into those areas.
6. Use a wash mitt or brush to clean hard-to-reach spots like the inside of the wheel wells, engine block, and rocker panels.
7. Remember to clean the door jambs, particularly the bottom part, where dirt accumulates, causing paint damage and rust.

Step 5: Drying and Protection

Once you’ve completed the deep cleaning process, it’s crucial to let everything dry thoroughly before applying protective coatings. Follow these steps:

1. Allow your car to air dry, or use a clean microfiber cloth to dry it completely.
2. Use this drying time to inspect the undercarriage for areas requiring touch-up paint or rust treatment.

Step 6: Applying Protective Coatings

To preserve the cleanliness and protect your car’s undercarriage, it’s recommended to apply two types of coatings: undercarriage dressing and WD-40.

1. Use a self-leveling undercarriage dressing, such as Adam’s Undercarriage Dressing, to protect the painted and metal surfaces. Follow the product instructions for the best application.
2. Spray a coat of WD-40 on the undercarriage, creating a protective barrier against rust and corrosion. Allow it to dry completely before driving the car.

Step 7: Tire and Fender Liner Care

Completing the cleaning process involves taking care of your tires and fender liners.

1. Clean your tires and wheels using a dedicated tire and rubber cleaner, such as Adam’s Tire and Rubber Cleaner.
2. Spray the cleaner onto the wheels and tires, allowing it to sit for a few minutes to break down brake dust and grime.
3. Agitate the cleaner using a brush or microfiber mitt.
4. Rinse off the cleaner thoroughly, ensuring all residue is removed.
5. Clean the fender liners using a brush and soap or an all-purpose cleaner. Pay special attention to fibrous fender liners that may require more scrubbing.

Step 8: Final Touches

With the wheels and tires clean, it’s time to add the finishing touches and protect the tires.

1. Apply a long-lasting tire dressing, such as Adam’s Tire Armor or a ceramic graphene tire coating, to protect and enhance the appearance of your tires. Follow the product instructions for the best results.
2. Allow the tire dressing to dry completely before installing the wheels back onto the car.

Summary and Key Points

1. Cleaning the undercarriage is essential to prevent rust and maintain the longevity of your car.
2. Start by cleaning the engine bay to avoid contamination of other areas.
3. Removing the wheels and fender liners provides better access and allows for a more thorough cleaning.
4. Pre-wash the undercarriage to soften dirt and grime before deep cleaning.
5. Use various tools, such as wash mitts and brushes, to clean hard-to-reach areas.
6. Be thorough and take time, ensuring every nook and cranny is free from dirt and debris.
7. Don’t forget to clean the door jambs and other areas prone to dirt buildup.
8. Allow the car to dry completely before applying protective coatings.
9. Apply undercarriage dressing and WD-40 to protect against rust and corrosion.
10. Take care of your tires and fender liners to complete the cleaning process.
11. Finish with a long-lasting tire dressing for added protection and a polished look.

Conclusion

Properly cleaning the underneath of your car is crucial for maintaining its appearance and preventing rust and corrosion. Following the step-by-step process outlined in this article, including pre-washing, deep cleaning, applying protective coatings, and regular maintenance, you can ensure that your car’s undercarriage remains in excellent condition for years.

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